Flow • Store • Support — Shallow Geocellular Drainage & Sub-base System

Manage stormwater at the source with ultra-shallow , traffic-rated modules. The high-strength structural alternative to aggregate sub-bases for permeable paving and podiums.

Request a concept design

See product pairings

Feature

≤ 30%

Drainage cost saving vs deep trenches

95%

Void ratio (storage & through-flow)

130 t/m²

Max vertical load (Honeycomb)

> 52%

Perforated intake area

50.2 → 94.2

L·s−1·m−2 layer discharge (0% → 2%)

≤ 60%

Irrigation saving via passive capillary

Applications

Capillary (Passive) Irrigation

The shallow, high‑void raft stores stormwater beneath the surface and passively lifts moisture into the root zone via capillary layers. Tunable outlets and inspection ports target a 24–48 hour drawdown, stabilising soil moisture and reducing potable irrigation.

Subsurface passive irrigation system using wicking cones for urban landscape watering

Tree Pit & Roads Protection

A load‑spreading, aerated shallow layer beneath paving around urban trees that distributes traffic loads, mitigates root heave, and passively supplies the root zone—improving pavement longevity and urban canopy health.

Geocellular tree root protection system preventing soil compaction under paved roads

LID Sub‑base Replacement

A lightweight, high‑void structural layer replacing part of the granular sub‑base. It bears surface loads while providing shallow storage and throttled discharge via underdrains/overflows and separator geotextiles.

Shallow attenuation tank as structural sub-base replacement for permeable block paving

Blue‑Green Roofs (Multifunctional Roofs)

A roof build‑up that couples roof‑level attenuation (“blue”) with vegetation (“green”). The shallow raft stores water and, with a capillary layer, maintains plant water security. Tunable outlets reduce peak flows and enable resilient, low‑energy landscapes.

Blue-green roof drainage layer with water storage on podium deck

System Selection Guide: Which Option fits your Site?

Both our systems function as a structural sub-base replacement with a 95% void ratio. They replace traditional aggregate to reduce excavation depth and handle traffic loads. Choose the right module based on your site’s depth and installation speed requirements.

Selection Criteria	Shallow Attenuation Tank	Honeycomb Drainage Cell
Module Height	Variable: 85, 150, 200, 250 mm (Fine-tune to exact invert levels)	Stackable: 82 mm increments (82, 164, 246 mm… Multi-layer capable)
Installation Speed	Fast: Hand-lay individual units	Ultra-Fast: Delivered in pre-assembled ≥9m² mats
Site Geometry	Flexible: Perfect for irregular shapes, curves, and tight corners.	Efficient: Best for large, open rectangular areas (Podiums/Car parks).
Load Capacity	Traffic Rated: Suitable for cars & light trucks.	High Load: Vertical strength ≥800 kN/m² for heavy duty.
Key Benefit	Maximum Volume Control in tight spots.	Speed of Installation on large decks.
	View Tank Details >>	View Tank Details >>

Design Principles & Performance Advantages

Hydraulic Logic

Storage per m² @150 mm ≈ 0.095 m³ (~95 L/m²); scalable by depth/area.

Target drawdown: 24–48 h; tuned via outlet geometry and head.

Surface‑proximal capture reduces inlet surcharge during cloudbursts.

Structural Performance

Load‑spreading raft for permeable paving, plazas, light‑traffic areas.

Uniform support under slabs/turf; separator geotextiles control fines.

Shallow cover depths; coordinate with freeze–thaw requirements.

Sustainability & Opex

Lower excavation and cart‑away; reduced imported aggregates.

Passive irrigation cuts potable use and pump energy.

Fewer deep utility conflicts; simplified maintenance access.

Multi‑dimensional Comparison

Dimension	Traditional Deep Pipes	Shallow Attenuation Raft
Excavation & Utilities	Deep trenches, utility conflicts, dewatering risks	Shallow build, minimal excavation, fewer utility clashes
Hydraulic Function	Conveyance‑led; limited on‑site storage	Integrated attenuation beneath surface; throttled discharge
Irrigation Capability	Separate systems/pumps required	Inherent passive irrigation via capillary layers
Resilience to Cloudbursts	Potential inlet surcharge; slower recovery	Rapid capture at source; 24–48 h repeatability
Programme & Cost	Longer programmes; more cart‑away/backfill	Faster install; reduced cart‑away; fewer materials
Carbon & Materials	High aggregate import; embodied carbon	Less aggregate; passive energy; lower embodied impacts
Retrofit Flexibility	Challenging in built‑up sites	Favourable for streetscapes, plazas, podium decks
Regulatory Context	Pipe‑centric; storage often separate	Aligns with SuDS (EU) & LID (US) emphasis on source control
Operations & Maintenance	Manholes and deep access requirements	Shallow inspection ports; easier access and flushing

Why Choose Shallow Attenuation?

Engineering‑led: design support, hydraulic modelling guidance, and build‑up details for each application.
SuDS/LID Ready: compatible with European SuDS manuals and North American LID/green infrastructure programs.
Cost & Programme: shallower excavation, fewer materials, accelerated installation, and predictable outflows.
Low‑Energy Operation: passive irrigation and gravity‑driven drawdown reduce energy and potable water demand.
Scalable & Modular: from small tree pits to large plazas and podium landscapes using standardized modules.

High-strength 150mm shallow geocellular module with 95% void ratio replacing traditional aggregate

System Integration

Stormwater cartridge filter for upstream silt and pollution control in SuDS systems

Aqua StormFilter

Cartridge/basket filtration upstream of the shallow raft to capture silt and hydrocarbons.

Talk To Engineer

Geocellular Tanks

High-volume detention modules used as downstream storage with throttled outlet control.

Stackable stormwater modules and soakaway crates for infiltration dry wells

Geocellular Modules

Decentralized soakaway cells linked to the raft for targeted infiltration and recharge.

Open-bottom plastic leaching chambers for septic drain fields and linear drainage

Stormwater Chambers

Accessible vault providing inspection, flushing and flow control for large catchments.

Geomembrane

Creates detention zones; use welded seams and protection layers per specification.

Geotextile

Filter/separator enabling infiltration while controlling fines (select weight & AOS by soil).

Drainage Cell

Thin-profile drainage panels for planters/podiums; interface with HydraCell for passive irrigation.

Talk To Engineer

HDPE twin-wall pipe for stormwater manifold connections and conveyance

SN8 Pipe

Outlet conveyance or bypass; connect via shallow inspection boxes with throttled discharge.

Talk To Engineer

FAQ

Q1: How do I choose between the Shallow Tank and Honeycomb Cell?

Answer: Choose the Shallow Tank (Box Type) when you need maximum storage volume in variable depths (85–250mm) or have an irregular site footprint. Choose the Honeycomb Cell (Panel Type) for large, flat areas like podiums or car parks where installation speed is critical (pre-assembled panels ≥9m²).

Q2: Can this system replace a traditional aggregate sub-base?

Answer: Yes. Both systems act as a high-strength structural sub-base replacement. They provide load-bearing support for permeable paving and traffic areas while creating 95% void space for water storage, eliminating the need for deep gravel layers.

Q3: What is the maximum traffic load rating?

Answer: Our systems are engineered for traffic. The Honeycomb Cell offers exceptional vertical strength (≥800 kN/m²), making it suitable for heavy-duty access roads. The Shallow Tank is rated for standard car parks and emergency vehicle access (H-20/H-25 equivalent) with appropriate cover.

Q4: Is it suitable for Blue-Green Roofs and podiums?

Answer: Absolutely. The ultra-shallow profile (82–85mm) is perfect for green roof drainage and podium deck attenuation. It protects the waterproofing layer and can be combined with wicking cones for passive irrigation.

Q5: How much excavation can I save?

Answer: Because of the 95% void ratio (compared to ~30% for gravel), you can typically reduce excavation depth by up to 30-50%. This saves significant costs on muck-away and imported fill.

Q6: Can I use it for tree root protection?

Answer: Yes. The system creates a load-bearing void that prevents soil compaction, allowing urban tree roots to breathe and grow freely under paved surfaces without causing damage.

Partner with us. Low input. High return. Full support.

Offer shallow geocellular rafts for depth-constrained sites—parking, streetscapes, and blue-green roofs—with engineer support and export-ready paperwork.

Become A Partner

Contact Sales

Solutions

Products

Become A Partner

About

Partner & Contact

Flow • Store • Support — Shallow Geocellular Drainage & Sub-base System

Feature

Applications

Capillary (Passive) Irrigation

Tree Pit & Roads Protection

LID Sub‑base Replacement

Blue‑Green Roofs (Multifunctional Roofs)

System Selection Guide: Which Option fits your Site?

Design Principles & Performance Advantages

Hydraulic Logic

Structural Performance

Sustainability & Opex

Multi‑dimensional Comparison

Why Choose Shallow Attenuation?

System Integration

Aqua StormFilter

Geocellular Tanks

Geocellular Modules

Stormwater Chambers

Geomembrane

Geotextile

Drainage Cell

SN8 Pipe

FAQ

Partner with us. Low input. High return. Full support.